Data centers may include several hundred or several thousand servers interconnected by high-speed switches and routers. Cloud data centers may provide a variety of services, such as web applications, e-mail services, search engine services, etc., for a plurality of customers. In recent years, data centers have transformed computing, with large scale consolidation of enterprise IT into data center hubs and with the emergence of cloud computing service providers.
Virtual machine (VM) technology allows one or more operating systems, or virtual machines, to run concurrently on one physical host, or physical machine. The advantages of virtual machine technology have become widely recognized. Among these advantages are the ability to run multiple virtual machines on a single host and the ability to migrate virtual machines from one host to another.
There is a need for cloud data centers to support multi-tenant or multi-organization network isolation while maintaining customer addresses across premises of various scopes. Customers need to move services from corporate networks to cloud data centers without disrupting services due to address renumbering, and data center administrators need the flexibility to migrate or consolidate work loads without reconfiguring the networks or disrupting services. To satisfy these requirements, cloud data centers need to accommodate potentially overlapping customer addresses.
In virtualized networks, a virtual machine may communicate with physical resources, such as storage devices, which are not virtualized. The physical resources may be located within the data center, at a customer location or at another data center. The physical resources may be dedicated to one customer or may be shared among customers. The virtual machine and the physical resources may utilize different addressing schemes.